Travel is joyful, eye-opening, and—yes—carbon intensive. The good news: once you understand where the emissions come from and what really moves the needle, you can still explore the world while dramatically shrinking your footprint.

Why the “carbon cost” of tourism matters

Tourism is responsible for a significant slice of global greenhouse gas emissions—often estimated between 8% and 11% of the world total when you account for transportation, accommodations, activities, and the supply chains that support them (Lenzen et al., 2018; Sun et al., 2023; WTTC, 2025). In 2019—the pre-pandemic peak—researchers estimate tourism’s footprint at roughly 5.2 gigatonnes CO₂-equivalent (CO₂e) (Lenzen et al., 2018; Sun et al., 2023). The United States plays an outsized role in that picture: combining Americans traveling and international visitors, U.S. tourism activity accounted for nearly 1 gigatonne CO₂ in 2019—about 19% of global tourism emissions (Sun et al., 2023).

Then came the pandemic. Emissions from travel cratered in 2020 as borders closed and skies emptied, with international arrivals down ~73% and inbound tourism emissions falling around 70% on average (UNWTO/MDPI, 2024; Stanford, 2021). But the respite was temporary. By 2023–2024, travel demand roared back. Sector analysis from the World Travel & Tourism Council indicates 2024 tourism activity surpassed 2019 economically, while emissions were ~9% lower—hinting at some efficiency gains and a slower return of the most carbon-intense segments (WTTC, 2025).

That’s the bird’s-eye view. What should travelers do with it? Let’s zoom in on where emissions really come from, how policies are reshaping options, and the smart choices that cut your footprint the most—without sacrificing the joy of the journey.

The big emitters: flights, driving, and cruising

Aviation: the Achilles’ heel

Per passenger-kilometer, flying is among the most carbon-intense ways to move. Short flights are worst (because takeoff and landing burn the most fuel), often around ~250 g CO₂/pkm; long-haul flights are more efficient per kilometer—roughly ~80–150 g CO₂/pkm—but total distances are so large that the footprint still balloons (EEA via Youmatter; ICCT, 2022). A single trans-U.S. flight can land close to ~0.8–1.0 t CO₂ per passenger in economy. And remember: high-altitude effects (contrails and NOx) roughly 1.5–3× the warming impact beyond CO₂ alone (Our World in Data, 2020).

In 2019, aviation contributed a bit over half of tourism’s direct emissions (UNWTO/ITF, 2019), which is why so many climate conversations focus on planes.

What travelers can do

• Fly less, stay longer. Reduce the number of long flights per year and stretch each trip.
• Swap short flights for trains (or buses) on feasible corridors; in many regions, trains can emit 5–20% of an equivalent flight’s CO₂ per passenger.
• Choose nonstop when possible. Fewer takeoffs/landings = less fuel burned.
• Economy over premium. Bigger seats mean fewer passengers per plane—your per-seat share of fuel rises.
• Support airlines investing in sustainable aviation fuel (SAF) and newer, more efficient fleets; if there’s an option to contribute to SAF purchases instead of offsets, that’s usually the stronger climate lever.

Driving: better with more people—and best with electrons

Cars are the second giant. A gasoline car with one occupant can emit ~200–250 g CO₂/km (EEA/EPA). At average U.S. occupancy (~1.5), that’s still ~170 g CO₂/pkm. But fill the seats, and the per-person footprint falls fast—~50–60 g CO₂/pkm with four people (EEA via Youmatter). Switch to an electric vehicle, and the emissions drop substantially—often 50–70% lower depending on the electricity mix (Our World in Data, 2020).

What travelers can do

• Carpool—family road trips are far more efficient than solo drives.
• Rent an EV where charging is reliable (increasingly common in the U.S. and Europe) or a hybrid if charging is uncertain.
• Drive gently (steady speeds, proper tire pressure) and pack light—small choices add up over hundreds of miles.

Cruising: a floating hotel… powered by heavy fuel

Large cruise ships are surprisingly carbon-intense per passenger-km—commonly ~250–300 g CO₂/pkm on modern vessels (ICCT, 2022). Even accounting for the avoided hotel stay, analysis suggests a cruise can emit around twice the CO₂ of a comparable fly-and-stay itinerary in some cases (ICCT, 2022). LNG can reduce local air pollutants but struggles to cut lifecycle GHG when methane leakage is included (ICCT, 2022).

What travelers can do

• If you love the sea, look for newer ships with shore-power hookups, slower itineraries (lower speeds burn less fuel), and operators trialing advanced efficiency measures.
• Consider ferries or sailing charters for island-hopping where feasible; ferries are typically less carbon-intense than big cruise ships and can beat short flights.

The low-carbon winners: trains and coaches

Electrified rail routinely delivers ~20–50 g CO₂/pkm, and high-speed networks on clean grids can be even lower. Intercity coaches (buses) also perform well, typically below ~70 g CO₂/pkm. In regions with robust rail (Europe, parts of Asia), shifting your trips from planes to trains is one of the biggest practical changes you can make as a traveler.

What policy is changing—and why it matters to you

While you can do a lot as an individual, policy decisions shape the menu of options you actually see when you book. Here are the big shifts—translated for travelers.

Aviation’s carbon guardrails are tightening (slowly)

• CORSIA (ICAO): International aviation’s carbon-offsetting scheme aims to cap net emissions at ~2020 levels by requiring airlines to offset growth above a baseline. It’s voluntary at first, moving to mandatory for most states in 2027. Not a silver bullet—but it sets a global floor and pushes better accounting.
• Sustainable Aviation Fuel (SAF): The EU’s ReFuelEU mandates rising SAF blends (2% in 2025 → 6% in 2030 → 70% in 2050). In the U.S., the SAF Grand Challenge targets 3 billion gallons/year by 2030, backed by tax credits. Expect more flights advertising SAF usage and checkout options to contribute.

Trains in, short flights out—at least in parts of Europe

• France’s short-haul flight restrictions ban certain domestic routes where a rail journey of 2.5 hours or less exists. Scope is narrow now, but it’s shifting behavior alongside rail investments.
• EU ETS for aviation is removing free allowances by 2026, making carbon a clearer cost and funding cleaner tech.
• Night trains and cross-border services are expanding again, providing more alternatives to short flights.

Cars: the electric transition helps road-trippers

EU rules phasing out new gas/diesel car sales by 2035 and U.S. incentives for EVs/charging mean your next rental, rideshare, or road trip is increasingly electric. Low-emission zones in major cities also nudge visitors toward transit, bikes, and walking.

Cruise and maritime rules are catching up

The IMO’s 2023 strategy points toward net-zero “by or around 2050,” with interim targets and efficiency ratings. More ports require shore power, letting ships switch off engines in harbor.

Bottom line for travelers: Expect to see more trains, clearer carbon information, and more electric options—and gradually higher prices on the most carbon-intense choices as carbon costs are internalized.

A practical playbook to shrink your travel footprint (without shrinking your joy)

Think of climate-savvy travel as Measure → Avoid → Shift → Improve—in that order. Here’s how to put that into practice.

1) Measure (get a quick sense of the big items)

• Flights dominate most international trip footprints.
• Hotel nights and car miles come next; food/activities are usually smaller.

Use a simple calculator to identify the one or two big decisions that matter most (mode or distance).

2) Avoid (the emissions you don’t create are the greenest)

• Bundle trips. Take one longer international trip instead of two short ones.
• Choose closer-to-home adventures every other trip.
• Leave gaps in your itinerary. Slow travel cuts intra-trip flights and frantic transfers.

3) Shift (choose lower-carbon modes and routes)

• Train beats plane on many sub-1,000 km routes; night trains = sleep + travel.
• Bus/coach can bridge cities where rail is limited.
• Drive electric when possible; otherwise carpool and pick an efficient vehicle.
• Pick nonstop flights when you must fly.
• Consider ferries vs short island hops by air.

4) Improve (cut intensity where you can’t avoid or shift)

• Pack lighter.
• Choose efficient stays (eco-labels, renewables, heat pumps, linen reuse).
• Eat local, plant-forward more often.
• Use public transit, walk, bike at your destination.
• Prefer SAF contributions or airline decarbonization programs over traditional offsets.

U.S. perspectives: what’s changing on “home turf”

SAF is the near-term lever for U.S. flyers

The SAF Grand Challenge and tax credits aim to scale alternatives to kerosene. Expect more domestic routes with SAF blends and options to contribute at checkout.

The great American road trip goes electric

Incentives and a growing national charging network make EV rentals and road trips increasingly practical. Many parks and gateway towns offer chargers and shuttle systems to cut congestion.

Rail: not Europe yet, but trending better

The Northeast Corridor continues to improve; projects like Brightline West (LA–Las Vegas) and long-term California HSR will make select intercity trips lower-carbon and time-competitive. Meanwhile, think Amtrak + bus combos for regional itineraries.

What travelers actually say—and how that translates to action

Surveys show strong intent to travel more sustainably—83% call it important, and 75% want to do more next year (Booking.com, 2024). Many also report that walking, biking, or taking transit enhances their trip.

But intentions meet reality: convenience, cost, and habit. “Flight shame” influenced behavior in parts of Europe, yet post-pandemic air travel rebounded strongly. The most reliable driver of change is better alternatives at competitive prices—fast trains, EV rentals priced like gas cars, etc.

Takeaway: Make one big choice (mode or distance) and two small choices (lodging and local mobility) each trip. Do it consistently and your footprint can drop by 30–60% year over year without quitting travel.

Putting it all together: three sample itineraries, re-imagined

Scenario 1: New York ↔ Paris, 7–10 days
Baseline: NYC–Paris roundtrip in economy, two intra-Europe short flights, standard hotel.
Lower-carbon plan: NYC–Paris nonstop; replace intra-Europe flights with TGV/Thalys trains; hotel with a credible eco-label; walk/metro.
Why it helps: Nonstop + rail can eliminate 2 takeoffs and 2 short-haul flights and cut accommodation energy intensity.

Scenario 2: Pacific Northwest road trip, 8 days
Baseline: Solo driving a mid-size gasoline SUV ~1,000 miles; conventional hotels.
Lower-carbon plan: EV rental (or hybrid); route around DC fast chargers; lodgings with renewables/efficiency; pack light; moderate speeds.
Why it helps: EV on the PNW grid often cuts ~50–70% of driving emissions; efficient stays tidy up the remainder.

Scenario 3: Mediterranean sun-seekers
Baseline: Fly into a hub, 5-night cruise, multiple port calls, fly out.
Lower-carbon plan: Fly into one coastal city; ferry to two nearby islands; locally owned lodging; slow pace.
Why it helps: Swapping a mega-ship for ferries and shore-based nights typically slashes per-km emissions and supports local economies more directly.

✈️🚆 Trip-by-Trip Carbon Planner for Climate-Savvy Travelers

A simple guide to measure, compare, and cut your travel emissions — trip by trip.

🧭 Step 1: Define Your Trip Profile

Before you start comparing modes, jot down the basics:

⚖️ Step 2: Estimate Transport Emissions

Use these average CO₂ emission factors (per passenger-kilometer, gCO₂/pkm):

Formula:
👉 Distance (km) × CO₂/pkm ÷ 1,000,000 = tonnes CO₂ per passenger

Example:
1,000 km short flight → 1,000 × 0.25 = 0.25 tonnes CO₂
1,000 km by train → 1,000 × 0.035 = 0.035 tonnes CO₂
✅ Train emits ~7× less.

🏨 Step 3: Add Accommodation Emissions

Formula:
👉 Nights × CO₂/night ÷ 1000 = tonnes CO₂

Example:
10 nights × 25 kg = 0.25 tonnes CO₂

🍴 Step 4: Add Food & Activities

Example:
10-day mixed diet + a few boat tours ≈ 0.07 tonnes CO₂

📊 Step 5: Add It Up

💡 Benchmark your total:
0.2–0.5 t CO₂ = Local / sustainable trip ✅
0.6–1.0 t = Medium-distance, moderate footprint ⚖️
1.5–3.0 t = Long-haul or cruise 🚨
>3 t = Carbon-heavy trip 🚫

🌱 Step 6: Apply “Measure → Avoid → Shift → Improve”

🧩 Example Planner in Action

Scenario: San Francisco → Tokyo, 14 days

🪄 Cutting impact:
Stay 3 weeks instead of 2 → fewer flights/year
Support SAF airline → −10%
Choose eco hotel → −30% lodging
Skip one domestic flight → −0.2 t
New total: ~2.8 t (−23%)

🌍 Bonus: Quick Reference Chart

💬 Planner Takeaway

“You don’t have to stop traveling; just travel better.
Pick fewer long flights, choose trains when possible, and make each journey count.”

With this planner, you can visualize your impact, make informed choices, and see real numbers—not guilt, but guidance.

Frequently asked questions (for curious, climate-savvy travelers)

1) Are carbon offsets worth buying?
Offsets have funded useful projects, but quality is uneven and they don’t avoid emissions at the source. If you must choose, prioritize SAF contributions (for flights), trains, and efficient lodgings. If you do buy offsets, pick high-integrity programs with robust verification and permanence.

2) Is it better to fly once and stay longer, or take multiple short trips?
One longer trip typically wins because long-haul flights dominate your footprint. Multiple trips add extra takeoffs and intra-trip flights.

3) Does premium cabin seating really increase my footprint?
Yes. Fewer seats per area means a larger per-passenger share of fuel. Economy or premium economy usually lowers your per-seat emissions.

4) Are trains always greener than planes?
Almost always on electrified networks. On coal-heavy grids the advantage narrows, but in Europe, Japan, and major North American corridors, trains are clear winners.

5) How can I identify a genuinely sustainable hotel?
Look for recognized labels (e.g., Green Key, LEED) and transparent reporting on energy, water, and waste. Industry data show hotel carbon intensity improved ~27% from 2014–2019 when properties invest.

6) Is cruising always “bad”?
It’s carbon-intense per passenger-km relative to many alternatives, and LNG’s lifecycle methane can blunt benefits. If you cruise, seek newer ships with shore power, slower itineraries, avoid energy-hungry amenities you won’t use, and compare against a ferry-plus-stay alternative.

A traveler’s pledge that actually moves the needle

Each year, I will (1) replace at least one flight with a train or road trip, (2) choose nonstop when I must fly, (3) stay longer and travel slower, and (4) book lodgings with credible sustainability practices.

It’s realistic, it compounds, and multiplied across millions of travelers, it meaningfully reduces tourism’s footprint—while keeping the magic of travel intact.

Final thoughts

Tourism won’t (and shouldn’t) disappear; it sustains livelihoods and fosters cultural understanding. But its carbon cost is real. The path forward is not guilt—it’s smarter choices supported by better systems: trains that are fast and comfortable, flights powered by cleaner fuels, road trips that are electric by default, and lodgings that sip, not guzzle, energy. Policy is making those choices more available; travelers are making them more popular. That’s how we preserve the world we’re so eager to explore.

References

• Booking.com (2024). Sustainable Travel Report 2024. news.booking.com
• Courthouse News (2023). European airlines drop vague promises on carbon offsets; shift toward SAF funds. courthousenews.com
• European Commission (2023). Reducing emissions from aviation (EU ETS, ReFuelEU). climate.ec.europa.eu
• ICCT (2022). Cruising and Flying: How do emissions compare? theicct.org
• ICAO (2016–2022). CORSIA explained. aviationbenefits.org
• Lenzen, M., et al. (2018). Nature Climate Change summary: The carbon footprint of global tourism. tourismemissions.org
• MDPI/UNWTO (2024). Transport-related CO₂ emissions of tourism & Glasgow Declaration updates. mdpi.com/…/2222
• OE/Greenview for Oxford Economics (2023). Hotel carbon efficiency improved 27% (2014–2019). oxfordeconomics.com
• Our World in Data (2020–2023). Carbon footprint of travel modes; non-CO₂ effects of aviation. ourworldindata.org
• Stanford (2021). COVID lockdown causes record drop in 2020 CO₂ emissions. sustainability.stanford.edu
• Sun, Y., et al. (2023). Nature Communications—global tourism emissions study (summary). theinvadingsea.com
• Tourism Analytics (2024). “Flight shame is dead”—debates on rebound and climate impacts. tourismanalytics.com
• UNWTO & ITF (2019). Transport-related CO₂ Emissions of Tourism. tourismemissions.org
• U.S. EPA (2021). Greenhouse Gas Emissions from a Typical Passenger Vehicle. epa.gov
• White House (2021). SAF Grand Challenge Fact Sheet. bidenwhitehouse.archives.gov
• For a comparative chart of mode emissions, see Our World in Data’s explainer on the carbon footprint of travel (link above).